1 // SPDX-License-Identifier: GPL-2.0+ 1 // SPDX-License-Identifier: GPL-2.0+
2 /* 2 /*
3 * Common functions for in-kernel torture test 3 * Common functions for in-kernel torture tests.
4 * 4 *
5 * Copyright (C) IBM Corporation, 2014 5 * Copyright (C) IBM Corporation, 2014
6 * 6 *
7 * Author: Paul E. McKenney <paulmck@linux.ibm 7 * Author: Paul E. McKenney <paulmck@linux.ibm.com>
8 * Based on kernel/rcu/torture.c. 8 * Based on kernel/rcu/torture.c.
9 */ 9 */
10 10
11 #define pr_fmt(fmt) fmt 11 #define pr_fmt(fmt) fmt
12 12
13 #include <linux/types.h> 13 #include <linux/types.h>
14 #include <linux/kernel.h> 14 #include <linux/kernel.h>
15 #include <linux/init.h> 15 #include <linux/init.h>
16 #include <linux/module.h> 16 #include <linux/module.h>
17 #include <linux/kthread.h> 17 #include <linux/kthread.h>
18 #include <linux/err.h> 18 #include <linux/err.h>
19 #include <linux/spinlock.h> 19 #include <linux/spinlock.h>
20 #include <linux/smp.h> 20 #include <linux/smp.h>
21 #include <linux/interrupt.h> 21 #include <linux/interrupt.h>
22 #include <linux/sched.h> 22 #include <linux/sched.h>
23 #include <linux/sched/clock.h> 23 #include <linux/sched/clock.h>
24 #include <linux/atomic.h> 24 #include <linux/atomic.h>
25 #include <linux/bitops.h> 25 #include <linux/bitops.h>
26 #include <linux/completion.h> 26 #include <linux/completion.h>
27 #include <linux/moduleparam.h> 27 #include <linux/moduleparam.h>
28 #include <linux/percpu.h> 28 #include <linux/percpu.h>
29 #include <linux/notifier.h> 29 #include <linux/notifier.h>
30 #include <linux/reboot.h> 30 #include <linux/reboot.h>
31 #include <linux/freezer.h> 31 #include <linux/freezer.h>
32 #include <linux/cpu.h> 32 #include <linux/cpu.h>
33 #include <linux/delay.h> 33 #include <linux/delay.h>
34 #include <linux/stat.h> 34 #include <linux/stat.h>
35 #include <linux/slab.h> 35 #include <linux/slab.h>
36 #include <linux/trace_clock.h> 36 #include <linux/trace_clock.h>
37 #include <linux/ktime.h> 37 #include <linux/ktime.h>
38 #include <asm/byteorder.h> 38 #include <asm/byteorder.h>
39 #include <linux/torture.h> 39 #include <linux/torture.h>
40 #include <linux/sched/rt.h> 40 #include <linux/sched/rt.h>
41 #include "rcu/rcu.h" 41 #include "rcu/rcu.h"
42 42
43 MODULE_DESCRIPTION("Common functions for in-ke <<
44 MODULE_LICENSE("GPL"); 43 MODULE_LICENSE("GPL");
45 MODULE_AUTHOR("Paul E. McKenney <paulmck@linux 44 MODULE_AUTHOR("Paul E. McKenney <paulmck@linux.ibm.com>");
46 45
47 static bool disable_onoff_at_boot; 46 static bool disable_onoff_at_boot;
48 module_param(disable_onoff_at_boot, bool, 0444 47 module_param(disable_onoff_at_boot, bool, 0444);
49 48
50 static bool ftrace_dump_at_shutdown; 49 static bool ftrace_dump_at_shutdown;
51 module_param(ftrace_dump_at_shutdown, bool, 04 50 module_param(ftrace_dump_at_shutdown, bool, 0444);
52 51
53 static int verbose_sleep_frequency; 52 static int verbose_sleep_frequency;
54 module_param(verbose_sleep_frequency, int, 044 53 module_param(verbose_sleep_frequency, int, 0444);
55 54
56 static int verbose_sleep_duration = 1; 55 static int verbose_sleep_duration = 1;
57 module_param(verbose_sleep_duration, int, 0444 56 module_param(verbose_sleep_duration, int, 0444);
58 57
59 static int random_shuffle; 58 static int random_shuffle;
60 module_param(random_shuffle, int, 0444); 59 module_param(random_shuffle, int, 0444);
61 60
62 static char *torture_type; 61 static char *torture_type;
63 static int verbose; 62 static int verbose;
64 63
65 /* Mediate rmmod and system shutdown. Concurr 64 /* Mediate rmmod and system shutdown. Concurrent rmmod & shutdown illegal! */
66 #define FULLSTOP_DONTSTOP 0 /* Normal oper 65 #define FULLSTOP_DONTSTOP 0 /* Normal operation. */
67 #define FULLSTOP_SHUTDOWN 1 /* System shut 66 #define FULLSTOP_SHUTDOWN 1 /* System shutdown with torture running. */
68 #define FULLSTOP_RMMOD 2 /* Normal rmmo 67 #define FULLSTOP_RMMOD 2 /* Normal rmmod of torture. */
69 static int fullstop = FULLSTOP_RMMOD; 68 static int fullstop = FULLSTOP_RMMOD;
70 static DEFINE_MUTEX(fullstop_mutex); 69 static DEFINE_MUTEX(fullstop_mutex);
71 70
72 static atomic_t verbose_sleep_counter; 71 static atomic_t verbose_sleep_counter;
73 72
74 /* 73 /*
75 * Sleep if needed from VERBOSE_TOROUT*(). 74 * Sleep if needed from VERBOSE_TOROUT*().
76 */ 75 */
77 void verbose_torout_sleep(void) 76 void verbose_torout_sleep(void)
78 { 77 {
79 if (verbose_sleep_frequency > 0 && 78 if (verbose_sleep_frequency > 0 &&
80 verbose_sleep_duration > 0 && 79 verbose_sleep_duration > 0 &&
81 !(atomic_inc_return(&verbose_sleep 80 !(atomic_inc_return(&verbose_sleep_counter) % verbose_sleep_frequency))
82 schedule_timeout_uninterruptib 81 schedule_timeout_uninterruptible(verbose_sleep_duration);
83 } 82 }
84 EXPORT_SYMBOL_GPL(verbose_torout_sleep); 83 EXPORT_SYMBOL_GPL(verbose_torout_sleep);
85 84
86 /* 85 /*
87 * Schedule a high-resolution-timer sleep in n 86 * Schedule a high-resolution-timer sleep in nanoseconds, with a 32-bit
88 * nanosecond random fuzz. This function and 87 * nanosecond random fuzz. This function and its friends desynchronize
89 * testing from the timer wheel. 88 * testing from the timer wheel.
90 */ 89 */
91 int torture_hrtimeout_ns(ktime_t baset_ns, u32 90 int torture_hrtimeout_ns(ktime_t baset_ns, u32 fuzzt_ns, const enum hrtimer_mode mode,
92 struct torture_random 91 struct torture_random_state *trsp)
93 { 92 {
94 ktime_t hto = baset_ns; 93 ktime_t hto = baset_ns;
95 94
96 if (trsp) 95 if (trsp)
97 hto += torture_random(trsp) % 96 hto += torture_random(trsp) % fuzzt_ns;
98 set_current_state(TASK_IDLE); 97 set_current_state(TASK_IDLE);
99 return schedule_hrtimeout(&hto, mode); 98 return schedule_hrtimeout(&hto, mode);
100 } 99 }
101 EXPORT_SYMBOL_GPL(torture_hrtimeout_ns); 100 EXPORT_SYMBOL_GPL(torture_hrtimeout_ns);
102 101
103 /* 102 /*
104 * Schedule a high-resolution-timer sleep in m 103 * Schedule a high-resolution-timer sleep in microseconds, with a 32-bit
105 * nanosecond (not microsecond!) random fuzz. 104 * nanosecond (not microsecond!) random fuzz.
106 */ 105 */
107 int torture_hrtimeout_us(u32 baset_us, u32 fuz 106 int torture_hrtimeout_us(u32 baset_us, u32 fuzzt_ns, struct torture_random_state *trsp)
108 { 107 {
109 ktime_t baset_ns = baset_us * NSEC_PER 108 ktime_t baset_ns = baset_us * NSEC_PER_USEC;
110 109
111 return torture_hrtimeout_ns(baset_ns, 110 return torture_hrtimeout_ns(baset_ns, fuzzt_ns, HRTIMER_MODE_REL, trsp);
112 } 111 }
113 EXPORT_SYMBOL_GPL(torture_hrtimeout_us); 112 EXPORT_SYMBOL_GPL(torture_hrtimeout_us);
114 113
115 /* 114 /*
116 * Schedule a high-resolution-timer sleep in m 115 * Schedule a high-resolution-timer sleep in milliseconds, with a 32-bit
117 * microsecond (not millisecond!) random fuzz. 116 * microsecond (not millisecond!) random fuzz.
118 */ 117 */
119 int torture_hrtimeout_ms(u32 baset_ms, u32 fuz 118 int torture_hrtimeout_ms(u32 baset_ms, u32 fuzzt_us, struct torture_random_state *trsp)
120 { 119 {
121 ktime_t baset_ns = baset_ms * NSEC_PER 120 ktime_t baset_ns = baset_ms * NSEC_PER_MSEC;
122 u32 fuzzt_ns; 121 u32 fuzzt_ns;
123 122
124 if ((u32)~0U / NSEC_PER_USEC < fuzzt_u 123 if ((u32)~0U / NSEC_PER_USEC < fuzzt_us)
125 fuzzt_ns = (u32)~0U; 124 fuzzt_ns = (u32)~0U;
126 else 125 else
127 fuzzt_ns = fuzzt_us * NSEC_PER 126 fuzzt_ns = fuzzt_us * NSEC_PER_USEC;
128 return torture_hrtimeout_ns(baset_ns, 127 return torture_hrtimeout_ns(baset_ns, fuzzt_ns, HRTIMER_MODE_REL, trsp);
129 } 128 }
130 EXPORT_SYMBOL_GPL(torture_hrtimeout_ms); 129 EXPORT_SYMBOL_GPL(torture_hrtimeout_ms);
131 130
132 /* 131 /*
133 * Schedule a high-resolution-timer sleep in j 132 * Schedule a high-resolution-timer sleep in jiffies, with an
134 * implied one-jiffy random fuzz. This is int 133 * implied one-jiffy random fuzz. This is intended to replace calls to
135 * schedule_timeout_interruptible() and friend 134 * schedule_timeout_interruptible() and friends.
136 */ 135 */
137 int torture_hrtimeout_jiffies(u32 baset_j, str 136 int torture_hrtimeout_jiffies(u32 baset_j, struct torture_random_state *trsp)
138 { 137 {
139 ktime_t baset_ns = jiffies_to_nsecs(ba 138 ktime_t baset_ns = jiffies_to_nsecs(baset_j);
140 139
141 return torture_hrtimeout_ns(baset_ns, 140 return torture_hrtimeout_ns(baset_ns, jiffies_to_nsecs(1), HRTIMER_MODE_REL, trsp);
142 } 141 }
143 EXPORT_SYMBOL_GPL(torture_hrtimeout_jiffies); 142 EXPORT_SYMBOL_GPL(torture_hrtimeout_jiffies);
144 143
145 /* 144 /*
146 * Schedule a high-resolution-timer sleep in m 145 * Schedule a high-resolution-timer sleep in milliseconds, with a 32-bit
147 * millisecond (not second!) random fuzz. 146 * millisecond (not second!) random fuzz.
148 */ 147 */
149 int torture_hrtimeout_s(u32 baset_s, u32 fuzzt 148 int torture_hrtimeout_s(u32 baset_s, u32 fuzzt_ms, struct torture_random_state *trsp)
150 { 149 {
151 ktime_t baset_ns = baset_s * NSEC_PER_ 150 ktime_t baset_ns = baset_s * NSEC_PER_SEC;
152 u32 fuzzt_ns; 151 u32 fuzzt_ns;
153 152
154 if ((u32)~0U / NSEC_PER_MSEC < fuzzt_m 153 if ((u32)~0U / NSEC_PER_MSEC < fuzzt_ms)
155 fuzzt_ns = (u32)~0U; 154 fuzzt_ns = (u32)~0U;
156 else 155 else
157 fuzzt_ns = fuzzt_ms * NSEC_PER 156 fuzzt_ns = fuzzt_ms * NSEC_PER_MSEC;
158 return torture_hrtimeout_ns(baset_ns, 157 return torture_hrtimeout_ns(baset_ns, fuzzt_ns, HRTIMER_MODE_REL, trsp);
159 } 158 }
160 EXPORT_SYMBOL_GPL(torture_hrtimeout_s); 159 EXPORT_SYMBOL_GPL(torture_hrtimeout_s);
161 160
162 #ifdef CONFIG_HOTPLUG_CPU 161 #ifdef CONFIG_HOTPLUG_CPU
163 162
164 /* 163 /*
165 * Variables for online-offline handling. Onl 164 * Variables for online-offline handling. Only present if CPU hotplug
166 * is enabled, otherwise does nothing. 165 * is enabled, otherwise does nothing.
167 */ 166 */
168 167
169 static struct task_struct *onoff_task; 168 static struct task_struct *onoff_task;
170 static long onoff_holdoff; 169 static long onoff_holdoff;
171 static long onoff_interval; 170 static long onoff_interval;
172 static torture_ofl_func *onoff_f; 171 static torture_ofl_func *onoff_f;
173 static long n_offline_attempts; 172 static long n_offline_attempts;
174 static long n_offline_successes; 173 static long n_offline_successes;
175 static unsigned long sum_offline; 174 static unsigned long sum_offline;
176 static int min_offline = -1; 175 static int min_offline = -1;
177 static int max_offline; 176 static int max_offline;
178 static long n_online_attempts; 177 static long n_online_attempts;
179 static long n_online_successes; 178 static long n_online_successes;
180 static unsigned long sum_online; 179 static unsigned long sum_online;
181 static int min_online = -1; 180 static int min_online = -1;
182 static int max_online; 181 static int max_online;
183 182
184 static int torture_online_cpus = NR_CPUS; 183 static int torture_online_cpus = NR_CPUS;
185 184
186 /* 185 /*
187 * Some torture testing leverages confusion as 186 * Some torture testing leverages confusion as to the number of online
188 * CPUs. This function returns the torture-te 187 * CPUs. This function returns the torture-testing view of this number,
189 * which allows torture tests to load-balance 188 * which allows torture tests to load-balance appropriately.
190 */ 189 */
191 int torture_num_online_cpus(void) 190 int torture_num_online_cpus(void)
192 { 191 {
193 return READ_ONCE(torture_online_cpus); 192 return READ_ONCE(torture_online_cpus);
194 } 193 }
195 EXPORT_SYMBOL_GPL(torture_num_online_cpus); 194 EXPORT_SYMBOL_GPL(torture_num_online_cpus);
196 195
197 /* 196 /*
198 * Attempt to take a CPU offline. Return fals 197 * Attempt to take a CPU offline. Return false if the CPU is already
199 * offline or if it is not subject to CPU-hotp 198 * offline or if it is not subject to CPU-hotplug operations. The
200 * caller can detect other failures by looking 199 * caller can detect other failures by looking at the statistics.
201 */ 200 */
202 bool torture_offline(int cpu, long *n_offl_att 201 bool torture_offline(int cpu, long *n_offl_attempts, long *n_offl_successes,
203 unsigned long *sum_offl, 202 unsigned long *sum_offl, int *min_offl, int *max_offl)
204 { 203 {
205 unsigned long delta; 204 unsigned long delta;
206 int ret; 205 int ret;
207 char *s; 206 char *s;
208 unsigned long starttime; 207 unsigned long starttime;
209 208
210 if (!cpu_online(cpu) || !cpu_is_hotplu 209 if (!cpu_online(cpu) || !cpu_is_hotpluggable(cpu))
211 return false; 210 return false;
212 if (num_online_cpus() <= 1) 211 if (num_online_cpus() <= 1)
213 return false; /* Can't offlin 212 return false; /* Can't offline the last CPU. */
214 213
215 if (verbose > 1) 214 if (verbose > 1)
216 pr_alert("%s" TORTURE_FLAG 215 pr_alert("%s" TORTURE_FLAG
217 "torture_onoff task: 216 "torture_onoff task: offlining %d\n",
218 torture_type, cpu); 217 torture_type, cpu);
219 starttime = jiffies; 218 starttime = jiffies;
220 (*n_offl_attempts)++; 219 (*n_offl_attempts)++;
221 ret = remove_cpu(cpu); 220 ret = remove_cpu(cpu);
222 if (ret) { 221 if (ret) {
223 s = ""; 222 s = "";
224 if (!rcu_inkernel_boot_has_end 223 if (!rcu_inkernel_boot_has_ended() && ret == -EBUSY) {
225 // PCI probe frequentl 224 // PCI probe frequently disables hotplug during boot.
226 (*n_offl_attempts)--; 225 (*n_offl_attempts)--;
227 s = " (-EBUSY forgiven 226 s = " (-EBUSY forgiven during boot)";
228 } 227 }
229 if (verbose) 228 if (verbose)
230 pr_alert("%s" TORTURE_ 229 pr_alert("%s" TORTURE_FLAG
231 "torture_onof 230 "torture_onoff task: offline %d failed%s: errno %d\n",
232 torture_type, 231 torture_type, cpu, s, ret);
233 } else { 232 } else {
234 if (verbose > 1) 233 if (verbose > 1)
235 pr_alert("%s" TORTURE_ 234 pr_alert("%s" TORTURE_FLAG
236 "torture_onof 235 "torture_onoff task: offlined %d\n",
237 torture_type, 236 torture_type, cpu);
238 if (onoff_f) 237 if (onoff_f)
239 onoff_f(); 238 onoff_f();
240 (*n_offl_successes)++; 239 (*n_offl_successes)++;
241 delta = jiffies - starttime; 240 delta = jiffies - starttime;
242 *sum_offl += delta; 241 *sum_offl += delta;
243 if (*min_offl < 0) { 242 if (*min_offl < 0) {
244 *min_offl = delta; 243 *min_offl = delta;
245 *max_offl = delta; 244 *max_offl = delta;
246 } 245 }
247 if (*min_offl > delta) 246 if (*min_offl > delta)
248 *min_offl = delta; 247 *min_offl = delta;
249 if (*max_offl < delta) 248 if (*max_offl < delta)
250 *max_offl = delta; 249 *max_offl = delta;
251 WRITE_ONCE(torture_online_cpus 250 WRITE_ONCE(torture_online_cpus, torture_online_cpus - 1);
252 WARN_ON_ONCE(torture_online_cp 251 WARN_ON_ONCE(torture_online_cpus <= 0);
253 } 252 }
254 253
255 return true; 254 return true;
256 } 255 }
257 EXPORT_SYMBOL_GPL(torture_offline); 256 EXPORT_SYMBOL_GPL(torture_offline);
258 257
259 /* 258 /*
260 * Attempt to bring a CPU online. Return fals 259 * Attempt to bring a CPU online. Return false if the CPU is already
261 * online or if it is not subject to CPU-hotpl 260 * online or if it is not subject to CPU-hotplug operations. The
262 * caller can detect other failures by looking 261 * caller can detect other failures by looking at the statistics.
263 */ 262 */
264 bool torture_online(int cpu, long *n_onl_attem 263 bool torture_online(int cpu, long *n_onl_attempts, long *n_onl_successes,
265 unsigned long *sum_onl, in 264 unsigned long *sum_onl, int *min_onl, int *max_onl)
266 { 265 {
267 unsigned long delta; 266 unsigned long delta;
268 int ret; 267 int ret;
269 char *s; 268 char *s;
270 unsigned long starttime; 269 unsigned long starttime;
271 270
272 if (cpu_online(cpu) || !cpu_is_hotplug 271 if (cpu_online(cpu) || !cpu_is_hotpluggable(cpu))
273 return false; 272 return false;
274 273
275 if (verbose > 1) 274 if (verbose > 1)
276 pr_alert("%s" TORTURE_FLAG 275 pr_alert("%s" TORTURE_FLAG
277 "torture_onoff task: 276 "torture_onoff task: onlining %d\n",
278 torture_type, cpu); 277 torture_type, cpu);
279 starttime = jiffies; 278 starttime = jiffies;
280 (*n_onl_attempts)++; 279 (*n_onl_attempts)++;
281 ret = add_cpu(cpu); 280 ret = add_cpu(cpu);
282 if (ret) { 281 if (ret) {
283 s = ""; 282 s = "";
284 if (!rcu_inkernel_boot_has_end 283 if (!rcu_inkernel_boot_has_ended() && ret == -EBUSY) {
285 // PCI probe frequentl 284 // PCI probe frequently disables hotplug during boot.
286 (*n_onl_attempts)--; 285 (*n_onl_attempts)--;
287 s = " (-EBUSY forgiven 286 s = " (-EBUSY forgiven during boot)";
288 } 287 }
289 if (verbose) 288 if (verbose)
290 pr_alert("%s" TORTURE_ 289 pr_alert("%s" TORTURE_FLAG
291 "torture_onof 290 "torture_onoff task: online %d failed%s: errno %d\n",
292 torture_type, 291 torture_type, cpu, s, ret);
293 } else { 292 } else {
294 if (verbose > 1) 293 if (verbose > 1)
295 pr_alert("%s" TORTURE_ 294 pr_alert("%s" TORTURE_FLAG
296 "torture_onof 295 "torture_onoff task: onlined %d\n",
297 torture_type, 296 torture_type, cpu);
298 (*n_onl_successes)++; 297 (*n_onl_successes)++;
299 delta = jiffies - starttime; 298 delta = jiffies - starttime;
300 *sum_onl += delta; 299 *sum_onl += delta;
301 if (*min_onl < 0) { 300 if (*min_onl < 0) {
302 *min_onl = delta; 301 *min_onl = delta;
303 *max_onl = delta; 302 *max_onl = delta;
304 } 303 }
305 if (*min_onl > delta) 304 if (*min_onl > delta)
306 *min_onl = delta; 305 *min_onl = delta;
307 if (*max_onl < delta) 306 if (*max_onl < delta)
308 *max_onl = delta; 307 *max_onl = delta;
309 WRITE_ONCE(torture_online_cpus 308 WRITE_ONCE(torture_online_cpus, torture_online_cpus + 1);
310 } 309 }
311 310
312 return true; 311 return true;
313 } 312 }
314 EXPORT_SYMBOL_GPL(torture_online); 313 EXPORT_SYMBOL_GPL(torture_online);
315 314
316 /* 315 /*
317 * Get everything online at the beginning and 316 * Get everything online at the beginning and ends of tests.
318 */ 317 */
319 static void torture_online_all(char *phase) 318 static void torture_online_all(char *phase)
320 { 319 {
321 int cpu; 320 int cpu;
322 int ret; 321 int ret;
323 322
324 for_each_possible_cpu(cpu) { 323 for_each_possible_cpu(cpu) {
325 if (cpu_online(cpu)) 324 if (cpu_online(cpu))
326 continue; 325 continue;
327 ret = add_cpu(cpu); 326 ret = add_cpu(cpu);
328 if (ret && verbose) { 327 if (ret && verbose) {
329 pr_alert("%s" TORTURE_ 328 pr_alert("%s" TORTURE_FLAG
330 "%s: %s onlin 329 "%s: %s online %d: errno %d\n",
331 __func__, pha 330 __func__, phase, torture_type, cpu, ret);
332 } 331 }
333 } 332 }
334 } 333 }
335 334
336 /* 335 /*
337 * Execute random CPU-hotplug operations at th 336 * Execute random CPU-hotplug operations at the interval specified
338 * by the onoff_interval. 337 * by the onoff_interval.
339 */ 338 */
340 static int 339 static int
341 torture_onoff(void *arg) 340 torture_onoff(void *arg)
342 { 341 {
343 int cpu; 342 int cpu;
344 int maxcpu = -1; 343 int maxcpu = -1;
345 DEFINE_TORTURE_RANDOM(rand); 344 DEFINE_TORTURE_RANDOM(rand);
346 345
347 VERBOSE_TOROUT_STRING("torture_onoff t 346 VERBOSE_TOROUT_STRING("torture_onoff task started");
348 for_each_online_cpu(cpu) 347 for_each_online_cpu(cpu)
349 maxcpu = cpu; 348 maxcpu = cpu;
350 WARN_ON(maxcpu < 0); 349 WARN_ON(maxcpu < 0);
351 torture_online_all("Initial"); 350 torture_online_all("Initial");
352 if (maxcpu == 0) { 351 if (maxcpu == 0) {
353 VERBOSE_TOROUT_STRING("Only on 352 VERBOSE_TOROUT_STRING("Only one CPU, so CPU-hotplug testing is disabled");
354 goto stop; 353 goto stop;
355 } 354 }
356 355
357 if (onoff_holdoff > 0) { 356 if (onoff_holdoff > 0) {
358 VERBOSE_TOROUT_STRING("torture 357 VERBOSE_TOROUT_STRING("torture_onoff begin holdoff");
359 torture_hrtimeout_jiffies(onof 358 torture_hrtimeout_jiffies(onoff_holdoff, &rand);
360 VERBOSE_TOROUT_STRING("torture 359 VERBOSE_TOROUT_STRING("torture_onoff end holdoff");
361 } 360 }
362 while (!torture_must_stop()) { 361 while (!torture_must_stop()) {
363 if (disable_onoff_at_boot && ! 362 if (disable_onoff_at_boot && !rcu_inkernel_boot_has_ended()) {
364 torture_hrtimeout_jiff 363 torture_hrtimeout_jiffies(HZ / 10, &rand);
365 continue; 364 continue;
366 } 365 }
367 cpu = torture_random(&rand) % 366 cpu = torture_random(&rand) % (maxcpu + 1);
368 if (!torture_offline(cpu, 367 if (!torture_offline(cpu,
369 &n_offlin 368 &n_offline_attempts, &n_offline_successes,
370 &sum_offl 369 &sum_offline, &min_offline, &max_offline))
371 torture_online(cpu, 370 torture_online(cpu,
372 &n_onli 371 &n_online_attempts, &n_online_successes,
373 &sum_on 372 &sum_online, &min_online, &max_online);
374 torture_hrtimeout_jiffies(onof 373 torture_hrtimeout_jiffies(onoff_interval, &rand);
375 } 374 }
376 375
377 stop: 376 stop:
378 torture_kthread_stopping("torture_onof 377 torture_kthread_stopping("torture_onoff");
379 torture_online_all("Final"); 378 torture_online_all("Final");
380 return 0; 379 return 0;
381 } 380 }
382 381
383 #endif /* #ifdef CONFIG_HOTPLUG_CPU */ 382 #endif /* #ifdef CONFIG_HOTPLUG_CPU */
384 383
385 /* 384 /*
386 * Initiate online-offline handling. 385 * Initiate online-offline handling.
387 */ 386 */
388 int torture_onoff_init(long ooholdoff, long oo 387 int torture_onoff_init(long ooholdoff, long oointerval, torture_ofl_func *f)
389 { 388 {
390 #ifdef CONFIG_HOTPLUG_CPU 389 #ifdef CONFIG_HOTPLUG_CPU
391 onoff_holdoff = ooholdoff; 390 onoff_holdoff = ooholdoff;
392 onoff_interval = oointerval; 391 onoff_interval = oointerval;
393 onoff_f = f; 392 onoff_f = f;
394 if (onoff_interval <= 0) 393 if (onoff_interval <= 0)
395 return 0; 394 return 0;
396 return torture_create_kthread(torture_ 395 return torture_create_kthread(torture_onoff, NULL, onoff_task);
397 #else /* #ifdef CONFIG_HOTPLUG_CPU */ 396 #else /* #ifdef CONFIG_HOTPLUG_CPU */
398 return 0; 397 return 0;
399 #endif /* #else #ifdef CONFIG_HOTPLUG_CPU */ 398 #endif /* #else #ifdef CONFIG_HOTPLUG_CPU */
400 } 399 }
401 EXPORT_SYMBOL_GPL(torture_onoff_init); 400 EXPORT_SYMBOL_GPL(torture_onoff_init);
402 401
403 /* 402 /*
404 * Clean up after online/offline testing. 403 * Clean up after online/offline testing.
405 */ 404 */
406 static void torture_onoff_cleanup(void) 405 static void torture_onoff_cleanup(void)
407 { 406 {
408 #ifdef CONFIG_HOTPLUG_CPU 407 #ifdef CONFIG_HOTPLUG_CPU
409 if (onoff_task == NULL) 408 if (onoff_task == NULL)
410 return; 409 return;
411 VERBOSE_TOROUT_STRING("Stopping tortur 410 VERBOSE_TOROUT_STRING("Stopping torture_onoff task");
412 kthread_stop(onoff_task); 411 kthread_stop(onoff_task);
413 onoff_task = NULL; 412 onoff_task = NULL;
414 #endif /* #ifdef CONFIG_HOTPLUG_CPU */ 413 #endif /* #ifdef CONFIG_HOTPLUG_CPU */
415 } 414 }
416 415
417 /* 416 /*
418 * Print online/offline testing statistics. 417 * Print online/offline testing statistics.
419 */ 418 */
420 void torture_onoff_stats(void) 419 void torture_onoff_stats(void)
421 { 420 {
422 #ifdef CONFIG_HOTPLUG_CPU 421 #ifdef CONFIG_HOTPLUG_CPU
423 pr_cont("onoff: %ld/%ld:%ld/%ld %d,%d: 422 pr_cont("onoff: %ld/%ld:%ld/%ld %d,%d:%d,%d %lu:%lu (HZ=%d) ",
424 n_online_successes, n_online_a 423 n_online_successes, n_online_attempts,
425 n_offline_successes, n_offline 424 n_offline_successes, n_offline_attempts,
426 min_online, max_online, 425 min_online, max_online,
427 min_offline, max_offline, 426 min_offline, max_offline,
428 sum_online, sum_offline, HZ); 427 sum_online, sum_offline, HZ);
429 #endif /* #ifdef CONFIG_HOTPLUG_CPU */ 428 #endif /* #ifdef CONFIG_HOTPLUG_CPU */
430 } 429 }
431 EXPORT_SYMBOL_GPL(torture_onoff_stats); 430 EXPORT_SYMBOL_GPL(torture_onoff_stats);
432 431
433 /* 432 /*
434 * Were all the online/offline operations succ 433 * Were all the online/offline operations successful?
435 */ 434 */
436 bool torture_onoff_failures(void) 435 bool torture_onoff_failures(void)
437 { 436 {
438 #ifdef CONFIG_HOTPLUG_CPU 437 #ifdef CONFIG_HOTPLUG_CPU
439 return n_online_successes != n_online_ 438 return n_online_successes != n_online_attempts ||
440 n_offline_successes != n_offlin 439 n_offline_successes != n_offline_attempts;
441 #else /* #ifdef CONFIG_HOTPLUG_CPU */ 440 #else /* #ifdef CONFIG_HOTPLUG_CPU */
442 return false; 441 return false;
443 #endif /* #else #ifdef CONFIG_HOTPLUG_CPU */ 442 #endif /* #else #ifdef CONFIG_HOTPLUG_CPU */
444 } 443 }
445 EXPORT_SYMBOL_GPL(torture_onoff_failures); 444 EXPORT_SYMBOL_GPL(torture_onoff_failures);
446 445
447 #define TORTURE_RANDOM_MULT 39916801 /* p 446 #define TORTURE_RANDOM_MULT 39916801 /* prime */
448 #define TORTURE_RANDOM_ADD 479001701 /* p 447 #define TORTURE_RANDOM_ADD 479001701 /* prime */
449 #define TORTURE_RANDOM_REFRESH 10000 448 #define TORTURE_RANDOM_REFRESH 10000
450 449
451 /* 450 /*
452 * Crude but fast random-number generator. Us 451 * Crude but fast random-number generator. Uses a linear congruential
453 * generator, with occasional help from cpu_cl 452 * generator, with occasional help from cpu_clock().
454 */ 453 */
455 unsigned long 454 unsigned long
456 torture_random(struct torture_random_state *tr 455 torture_random(struct torture_random_state *trsp)
457 { 456 {
458 if (--trsp->trs_count < 0) { 457 if (--trsp->trs_count < 0) {
459 trsp->trs_state += (unsigned l 458 trsp->trs_state += (unsigned long)local_clock() + raw_smp_processor_id();
460 trsp->trs_count = TORTURE_RAND 459 trsp->trs_count = TORTURE_RANDOM_REFRESH;
461 } 460 }
462 trsp->trs_state = trsp->trs_state * TO 461 trsp->trs_state = trsp->trs_state * TORTURE_RANDOM_MULT +
463 TORTURE_RANDOM_ADD; 462 TORTURE_RANDOM_ADD;
464 return swahw32(trsp->trs_state); 463 return swahw32(trsp->trs_state);
465 } 464 }
466 EXPORT_SYMBOL_GPL(torture_random); 465 EXPORT_SYMBOL_GPL(torture_random);
467 466
468 /* 467 /*
469 * Variables for shuffling. The idea is to en 468 * Variables for shuffling. The idea is to ensure that each CPU stays
470 * idle for an extended period to test interac 469 * idle for an extended period to test interactions with dyntick idle,
471 * as well as interactions with any per-CPU va 470 * as well as interactions with any per-CPU variables.
472 */ 471 */
473 struct shuffle_task { 472 struct shuffle_task {
474 struct list_head st_l; 473 struct list_head st_l;
475 struct task_struct *st_t; 474 struct task_struct *st_t;
476 }; 475 };
477 476
478 static long shuffle_interval; /* In jiffies. 477 static long shuffle_interval; /* In jiffies. */
479 static struct task_struct *shuffler_task; 478 static struct task_struct *shuffler_task;
480 static cpumask_var_t shuffle_tmp_mask; 479 static cpumask_var_t shuffle_tmp_mask;
481 static int shuffle_idle_cpu; /* Force all t 480 static int shuffle_idle_cpu; /* Force all torture tasks off this CPU */
482 static struct list_head shuffle_task_list = LI 481 static struct list_head shuffle_task_list = LIST_HEAD_INIT(shuffle_task_list);
483 static DEFINE_MUTEX(shuffle_task_mutex); 482 static DEFINE_MUTEX(shuffle_task_mutex);
484 483
485 /* 484 /*
486 * Register a task to be shuffled. If there i 485 * Register a task to be shuffled. If there is no memory, just splat
487 * and don't bother registering. 486 * and don't bother registering.
488 */ 487 */
489 void torture_shuffle_task_register(struct task 488 void torture_shuffle_task_register(struct task_struct *tp)
490 { 489 {
491 struct shuffle_task *stp; 490 struct shuffle_task *stp;
492 491
493 if (WARN_ON_ONCE(tp == NULL)) 492 if (WARN_ON_ONCE(tp == NULL))
494 return; 493 return;
495 stp = kmalloc(sizeof(*stp), GFP_KERNEL 494 stp = kmalloc(sizeof(*stp), GFP_KERNEL);
496 if (WARN_ON_ONCE(stp == NULL)) 495 if (WARN_ON_ONCE(stp == NULL))
497 return; 496 return;
498 stp->st_t = tp; 497 stp->st_t = tp;
499 mutex_lock(&shuffle_task_mutex); 498 mutex_lock(&shuffle_task_mutex);
500 list_add(&stp->st_l, &shuffle_task_lis 499 list_add(&stp->st_l, &shuffle_task_list);
501 mutex_unlock(&shuffle_task_mutex); 500 mutex_unlock(&shuffle_task_mutex);
502 } 501 }
503 EXPORT_SYMBOL_GPL(torture_shuffle_task_registe 502 EXPORT_SYMBOL_GPL(torture_shuffle_task_register);
504 503
505 /* 504 /*
506 * Unregister all tasks, for example, at the e 505 * Unregister all tasks, for example, at the end of the torture run.
507 */ 506 */
508 static void torture_shuffle_task_unregister_al 507 static void torture_shuffle_task_unregister_all(void)
509 { 508 {
510 struct shuffle_task *stp; 509 struct shuffle_task *stp;
511 struct shuffle_task *p; 510 struct shuffle_task *p;
512 511
513 mutex_lock(&shuffle_task_mutex); 512 mutex_lock(&shuffle_task_mutex);
514 list_for_each_entry_safe(stp, p, &shuf 513 list_for_each_entry_safe(stp, p, &shuffle_task_list, st_l) {
515 list_del(&stp->st_l); 514 list_del(&stp->st_l);
516 kfree(stp); 515 kfree(stp);
517 } 516 }
518 mutex_unlock(&shuffle_task_mutex); 517 mutex_unlock(&shuffle_task_mutex);
519 } 518 }
520 519
521 /* Shuffle tasks such that we allow shuffle_id 520 /* Shuffle tasks such that we allow shuffle_idle_cpu to become idle.
522 * A special case is when shuffle_idle_cpu = - 521 * A special case is when shuffle_idle_cpu = -1, in which case we allow
523 * the tasks to run on all CPUs. 522 * the tasks to run on all CPUs.
524 */ 523 */
525 static void torture_shuffle_tasks(struct tortu 524 static void torture_shuffle_tasks(struct torture_random_state *trp)
526 { 525 {
527 struct shuffle_task *stp; 526 struct shuffle_task *stp;
528 527
529 cpumask_setall(shuffle_tmp_mask); 528 cpumask_setall(shuffle_tmp_mask);
530 cpus_read_lock(); 529 cpus_read_lock();
531 530
532 /* No point in shuffling if there is o 531 /* No point in shuffling if there is only one online CPU (ex: UP) */
533 if (num_online_cpus() == 1) { 532 if (num_online_cpus() == 1) {
534 cpus_read_unlock(); 533 cpus_read_unlock();
535 return; 534 return;
536 } 535 }
537 536
538 /* Advance to the next CPU. Upon over 537 /* Advance to the next CPU. Upon overflow, don't idle any CPUs. */
539 shuffle_idle_cpu = cpumask_next(shuffl 538 shuffle_idle_cpu = cpumask_next(shuffle_idle_cpu, shuffle_tmp_mask);
540 if (shuffle_idle_cpu >= nr_cpu_ids) 539 if (shuffle_idle_cpu >= nr_cpu_ids)
541 shuffle_idle_cpu = -1; 540 shuffle_idle_cpu = -1;
542 else 541 else
543 cpumask_clear_cpu(shuffle_idle 542 cpumask_clear_cpu(shuffle_idle_cpu, shuffle_tmp_mask);
544 543
545 mutex_lock(&shuffle_task_mutex); 544 mutex_lock(&shuffle_task_mutex);
546 list_for_each_entry(stp, &shuffle_task 545 list_for_each_entry(stp, &shuffle_task_list, st_l) {
547 if (!random_shuffle || torture 546 if (!random_shuffle || torture_random(trp) & 0x1)
548 set_cpus_allowed_ptr(s 547 set_cpus_allowed_ptr(stp->st_t, shuffle_tmp_mask);
549 } 548 }
550 mutex_unlock(&shuffle_task_mutex); 549 mutex_unlock(&shuffle_task_mutex);
551 550
552 cpus_read_unlock(); 551 cpus_read_unlock();
553 } 552 }
554 553
555 /* Shuffle tasks across CPUs, with the intent 554 /* Shuffle tasks across CPUs, with the intent of allowing each CPU in the
556 * system to become idle at a time and cut off 555 * system to become idle at a time and cut off its timer ticks. This is meant
557 * to test the support for such tickless idle 556 * to test the support for such tickless idle CPU in RCU.
558 */ 557 */
559 static int torture_shuffle(void *arg) 558 static int torture_shuffle(void *arg)
560 { 559 {
561 DEFINE_TORTURE_RANDOM(rand); 560 DEFINE_TORTURE_RANDOM(rand);
562 561
563 VERBOSE_TOROUT_STRING("torture_shuffle 562 VERBOSE_TOROUT_STRING("torture_shuffle task started");
564 do { 563 do {
565 torture_hrtimeout_jiffies(shuf 564 torture_hrtimeout_jiffies(shuffle_interval, &rand);
566 torture_shuffle_tasks(&rand); 565 torture_shuffle_tasks(&rand);
567 torture_shutdown_absorb("tortu 566 torture_shutdown_absorb("torture_shuffle");
568 } while (!torture_must_stop()); 567 } while (!torture_must_stop());
569 torture_kthread_stopping("torture_shuf 568 torture_kthread_stopping("torture_shuffle");
570 return 0; 569 return 0;
571 } 570 }
572 571
573 /* 572 /*
574 * Start the shuffler, with shuffint in jiffie 573 * Start the shuffler, with shuffint in jiffies.
575 */ 574 */
576 int torture_shuffle_init(long shuffint) 575 int torture_shuffle_init(long shuffint)
577 { 576 {
578 shuffle_interval = shuffint; 577 shuffle_interval = shuffint;
579 578
580 shuffle_idle_cpu = -1; 579 shuffle_idle_cpu = -1;
581 580
582 if (!alloc_cpumask_var(&shuffle_tmp_ma 581 if (!alloc_cpumask_var(&shuffle_tmp_mask, GFP_KERNEL)) {
583 TOROUT_ERRSTRING("Failed to al 582 TOROUT_ERRSTRING("Failed to alloc mask");
584 return -ENOMEM; 583 return -ENOMEM;
585 } 584 }
586 585
587 /* Create the shuffler thread */ 586 /* Create the shuffler thread */
588 return torture_create_kthread(torture_ 587 return torture_create_kthread(torture_shuffle, NULL, shuffler_task);
589 } 588 }
590 EXPORT_SYMBOL_GPL(torture_shuffle_init); 589 EXPORT_SYMBOL_GPL(torture_shuffle_init);
591 590
592 /* 591 /*
593 * Stop the shuffling. 592 * Stop the shuffling.
594 */ 593 */
595 static void torture_shuffle_cleanup(void) 594 static void torture_shuffle_cleanup(void)
596 { 595 {
597 torture_shuffle_task_unregister_all(); 596 torture_shuffle_task_unregister_all();
598 if (shuffler_task) { 597 if (shuffler_task) {
599 VERBOSE_TOROUT_STRING("Stoppin 598 VERBOSE_TOROUT_STRING("Stopping torture_shuffle task");
600 kthread_stop(shuffler_task); 599 kthread_stop(shuffler_task);
601 free_cpumask_var(shuffle_tmp_m 600 free_cpumask_var(shuffle_tmp_mask);
602 } 601 }
603 shuffler_task = NULL; 602 shuffler_task = NULL;
604 } 603 }
605 604
606 /* 605 /*
607 * Variables for auto-shutdown. This allows " 606 * Variables for auto-shutdown. This allows "lights out" torture runs
608 * to be fully scripted. 607 * to be fully scripted.
609 */ 608 */
610 static struct task_struct *shutdown_task; 609 static struct task_struct *shutdown_task;
611 static ktime_t shutdown_time; /* tim 610 static ktime_t shutdown_time; /* time to system shutdown. */
612 static void (*torture_shutdown_hook)(void); 611 static void (*torture_shutdown_hook)(void);
613 612
614 /* 613 /*
615 * Absorb kthreads into a kernel function that 614 * Absorb kthreads into a kernel function that won't return, so that
616 * they won't ever access module text or data 615 * they won't ever access module text or data again.
617 */ 616 */
618 void torture_shutdown_absorb(const char *title 617 void torture_shutdown_absorb(const char *title)
619 { 618 {
620 while (READ_ONCE(fullstop) == FULLSTOP 619 while (READ_ONCE(fullstop) == FULLSTOP_SHUTDOWN) {
621 pr_notice("torture thread %s p 620 pr_notice("torture thread %s parking due to system shutdown\n",
622 title); 621 title);
623 schedule_timeout_uninterruptib 622 schedule_timeout_uninterruptible(MAX_SCHEDULE_TIMEOUT);
624 } 623 }
625 } 624 }
626 EXPORT_SYMBOL_GPL(torture_shutdown_absorb); 625 EXPORT_SYMBOL_GPL(torture_shutdown_absorb);
627 626
628 /* 627 /*
629 * Cause the torture test to shutdown the syst 628 * Cause the torture test to shutdown the system after the test has
630 * run for the time specified by the shutdown_ 629 * run for the time specified by the shutdown_secs parameter.
631 */ 630 */
632 static int torture_shutdown(void *arg) 631 static int torture_shutdown(void *arg)
633 { 632 {
634 ktime_t ktime_snap; 633 ktime_t ktime_snap;
635 634
636 VERBOSE_TOROUT_STRING("torture_shutdow 635 VERBOSE_TOROUT_STRING("torture_shutdown task started");
637 ktime_snap = ktime_get(); 636 ktime_snap = ktime_get();
638 while (ktime_before(ktime_snap, shutdo 637 while (ktime_before(ktime_snap, shutdown_time) &&
639 !torture_must_stop()) { 638 !torture_must_stop()) {
640 if (verbose) 639 if (verbose)
641 pr_alert("%s" TORTURE_ 640 pr_alert("%s" TORTURE_FLAG
642 "torture_shut 641 "torture_shutdown task: %llu ms remaining\n",
643 torture_type, 642 torture_type,
644 ktime_ms_delt 643 ktime_ms_delta(shutdown_time, ktime_snap));
645 set_current_state(TASK_INTERRU 644 set_current_state(TASK_INTERRUPTIBLE);
646 schedule_hrtimeout(&shutdown_t 645 schedule_hrtimeout(&shutdown_time, HRTIMER_MODE_ABS);
647 ktime_snap = ktime_get(); 646 ktime_snap = ktime_get();
648 } 647 }
649 if (torture_must_stop()) { 648 if (torture_must_stop()) {
650 torture_kthread_stopping("tort 649 torture_kthread_stopping("torture_shutdown");
651 return 0; 650 return 0;
652 } 651 }
653 652
654 /* OK, shut down the system. */ 653 /* OK, shut down the system. */
655 654
656 VERBOSE_TOROUT_STRING("torture_shutdow 655 VERBOSE_TOROUT_STRING("torture_shutdown task shutting down system");
657 shutdown_task = NULL; /* Avoid self- 656 shutdown_task = NULL; /* Avoid self-kill deadlock. */
658 if (torture_shutdown_hook) 657 if (torture_shutdown_hook)
659 torture_shutdown_hook(); 658 torture_shutdown_hook();
660 else 659 else
661 VERBOSE_TOROUT_STRING("No tort 660 VERBOSE_TOROUT_STRING("No torture_shutdown_hook(), skipping.");
662 if (ftrace_dump_at_shutdown) 661 if (ftrace_dump_at_shutdown)
663 rcu_ftrace_dump(DUMP_ALL); 662 rcu_ftrace_dump(DUMP_ALL);
664 kernel_power_off(); /* Shut down t 663 kernel_power_off(); /* Shut down the system. */
665 return 0; 664 return 0;
666 } 665 }
667 666
668 /* 667 /*
669 * Start up the shutdown task. 668 * Start up the shutdown task.
670 */ 669 */
671 int torture_shutdown_init(int ssecs, void (*cl 670 int torture_shutdown_init(int ssecs, void (*cleanup)(void))
672 { 671 {
673 torture_shutdown_hook = cleanup; 672 torture_shutdown_hook = cleanup;
674 if (ssecs > 0) { 673 if (ssecs > 0) {
675 shutdown_time = ktime_add(ktim 674 shutdown_time = ktime_add(ktime_get(), ktime_set(ssecs, 0));
676 return torture_create_kthread( 675 return torture_create_kthread(torture_shutdown, NULL,
677 676 shutdown_task);
678 } 677 }
679 return 0; 678 return 0;
680 } 679 }
681 EXPORT_SYMBOL_GPL(torture_shutdown_init); 680 EXPORT_SYMBOL_GPL(torture_shutdown_init);
682 681
683 /* 682 /*
684 * Detect and respond to a system shutdown. 683 * Detect and respond to a system shutdown.
685 */ 684 */
686 static int torture_shutdown_notify(struct noti 685 static int torture_shutdown_notify(struct notifier_block *unused1,
687 unsigned lo 686 unsigned long unused2, void *unused3)
688 { 687 {
689 mutex_lock(&fullstop_mutex); 688 mutex_lock(&fullstop_mutex);
690 if (READ_ONCE(fullstop) == FULLSTOP_DO 689 if (READ_ONCE(fullstop) == FULLSTOP_DONTSTOP) {
691 VERBOSE_TOROUT_STRING("Unsched 690 VERBOSE_TOROUT_STRING("Unscheduled system shutdown detected");
692 WRITE_ONCE(fullstop, FULLSTOP_ 691 WRITE_ONCE(fullstop, FULLSTOP_SHUTDOWN);
693 } else { 692 } else {
694 pr_warn("Concurrent rmmod and 693 pr_warn("Concurrent rmmod and shutdown illegal!\n");
695 } 694 }
696 mutex_unlock(&fullstop_mutex); 695 mutex_unlock(&fullstop_mutex);
697 return NOTIFY_DONE; 696 return NOTIFY_DONE;
698 } 697 }
699 698
700 static struct notifier_block torture_shutdown_ 699 static struct notifier_block torture_shutdown_nb = {
701 .notifier_call = torture_shutdown_noti 700 .notifier_call = torture_shutdown_notify,
702 }; 701 };
703 702
704 /* 703 /*
705 * Shut down the shutdown task. Say what??? 704 * Shut down the shutdown task. Say what??? Heh! This can happen if
706 * the torture module gets an rmmod before the 705 * the torture module gets an rmmod before the shutdown time arrives. ;-)
707 */ 706 */
708 static void torture_shutdown_cleanup(void) 707 static void torture_shutdown_cleanup(void)
709 { 708 {
710 unregister_reboot_notifier(&torture_sh 709 unregister_reboot_notifier(&torture_shutdown_nb);
711 if (shutdown_task != NULL) { 710 if (shutdown_task != NULL) {
712 VERBOSE_TOROUT_STRING("Stoppin 711 VERBOSE_TOROUT_STRING("Stopping torture_shutdown task");
713 kthread_stop(shutdown_task); 712 kthread_stop(shutdown_task);
714 } 713 }
715 shutdown_task = NULL; 714 shutdown_task = NULL;
716 } 715 }
717 716
718 /* 717 /*
719 * Variables for stuttering, which means to pe 718 * Variables for stuttering, which means to periodically pause and
720 * restart testing in order to catch bugs that 719 * restart testing in order to catch bugs that appear when load is
721 * suddenly applied to or removed from the sys 720 * suddenly applied to or removed from the system.
722 */ 721 */
723 static struct task_struct *stutter_task; 722 static struct task_struct *stutter_task;
724 static ktime_t stutter_till_abs_time; 723 static ktime_t stutter_till_abs_time;
725 static int stutter; 724 static int stutter;
726 static int stutter_gap; 725 static int stutter_gap;
727 726
728 /* 727 /*
729 * Block until the stutter interval ends. Thi 728 * Block until the stutter interval ends. This must be called periodically
730 * by all running kthreads that need to be sub 729 * by all running kthreads that need to be subject to stuttering.
731 */ 730 */
732 bool stutter_wait(const char *title) 731 bool stutter_wait(const char *title)
733 { 732 {
734 bool ret = false; 733 bool ret = false;
735 ktime_t till_ns; 734 ktime_t till_ns;
736 735
737 cond_resched_tasks_rcu_qs(); 736 cond_resched_tasks_rcu_qs();
738 till_ns = READ_ONCE(stutter_till_abs_t 737 till_ns = READ_ONCE(stutter_till_abs_time);
739 if (till_ns && ktime_before(ktime_get( 738 if (till_ns && ktime_before(ktime_get(), till_ns)) {
740 torture_hrtimeout_ns(till_ns, 739 torture_hrtimeout_ns(till_ns, 0, HRTIMER_MODE_ABS, NULL);
741 ret = true; 740 ret = true;
742 } 741 }
743 torture_shutdown_absorb(title); 742 torture_shutdown_absorb(title);
744 return ret; 743 return ret;
745 } 744 }
746 EXPORT_SYMBOL_GPL(stutter_wait); 745 EXPORT_SYMBOL_GPL(stutter_wait);
747 746
748 /* 747 /*
749 * Cause the torture test to "stutter", starti 748 * Cause the torture test to "stutter", starting and stopping all
750 * threads periodically. 749 * threads periodically.
751 */ 750 */
752 static int torture_stutter(void *arg) 751 static int torture_stutter(void *arg)
753 { 752 {
754 ktime_t till_ns; 753 ktime_t till_ns;
755 754
756 VERBOSE_TOROUT_STRING("torture_stutter 755 VERBOSE_TOROUT_STRING("torture_stutter task started");
757 do { 756 do {
758 if (!torture_must_stop() && st 757 if (!torture_must_stop() && stutter > 1) {
759 till_ns = ktime_add_ns 758 till_ns = ktime_add_ns(ktime_get(),
760 759 jiffies_to_nsecs(stutter));
761 WRITE_ONCE(stutter_til 760 WRITE_ONCE(stutter_till_abs_time, till_ns);
762 torture_hrtimeout_jiff 761 torture_hrtimeout_jiffies(stutter - 1, NULL);
763 } 762 }
764 if (!torture_must_stop()) 763 if (!torture_must_stop())
765 torture_hrtimeout_jiff 764 torture_hrtimeout_jiffies(stutter_gap, NULL);
766 torture_shutdown_absorb("tortu 765 torture_shutdown_absorb("torture_stutter");
767 } while (!torture_must_stop()); 766 } while (!torture_must_stop());
768 torture_kthread_stopping("torture_stut 767 torture_kthread_stopping("torture_stutter");
769 return 0; 768 return 0;
770 } 769 }
771 770
772 /* 771 /*
773 * Initialize and kick off the torture_stutter 772 * Initialize and kick off the torture_stutter kthread.
774 */ 773 */
775 int torture_stutter_init(const int s, const in 774 int torture_stutter_init(const int s, const int sgap)
776 { 775 {
777 stutter = s; 776 stutter = s;
778 stutter_gap = sgap; 777 stutter_gap = sgap;
779 return torture_create_kthread(torture_ 778 return torture_create_kthread(torture_stutter, NULL, stutter_task);
780 } 779 }
781 EXPORT_SYMBOL_GPL(torture_stutter_init); 780 EXPORT_SYMBOL_GPL(torture_stutter_init);
782 781
783 /* 782 /*
784 * Cleanup after the torture_stutter kthread. 783 * Cleanup after the torture_stutter kthread.
785 */ 784 */
786 static void torture_stutter_cleanup(void) 785 static void torture_stutter_cleanup(void)
787 { 786 {
788 if (!stutter_task) 787 if (!stutter_task)
789 return; 788 return;
790 VERBOSE_TOROUT_STRING("Stopping tortur 789 VERBOSE_TOROUT_STRING("Stopping torture_stutter task");
791 kthread_stop(stutter_task); 790 kthread_stop(stutter_task);
792 stutter_task = NULL; 791 stutter_task = NULL;
793 } 792 }
794 793
795 static void 794 static void
796 torture_print_module_parms(void) 795 torture_print_module_parms(void)
797 { 796 {
798 pr_alert("torture module --- %s: disa 797 pr_alert("torture module --- %s: disable_onoff_at_boot=%d ftrace_dump_at_shutdown=%d verbose_sleep_frequency=%d verbose_sleep_duration=%d random_shuffle=%d\n",
799 torture_type, disable_onoff_a 798 torture_type, disable_onoff_at_boot, ftrace_dump_at_shutdown, verbose_sleep_frequency, verbose_sleep_duration, random_shuffle);
800 } 799 }
801 800
802 /* 801 /*
803 * Initialize torture module. Please note tha 802 * Initialize torture module. Please note that this is -not- invoked via
804 * the usual module_init() mechanism, but rath 803 * the usual module_init() mechanism, but rather by an explicit call from
805 * the client torture module. This call must 804 * the client torture module. This call must be paired with a later
806 * torture_init_end(). 805 * torture_init_end().
807 * 806 *
808 * The runnable parameter points to a flag tha 807 * The runnable parameter points to a flag that controls whether or not
809 * the test is currently runnable. If there i 808 * the test is currently runnable. If there is no such flag, pass in NULL.
810 */ 809 */
811 bool torture_init_begin(char *ttype, int v) 810 bool torture_init_begin(char *ttype, int v)
812 { 811 {
813 mutex_lock(&fullstop_mutex); 812 mutex_lock(&fullstop_mutex);
814 if (torture_type != NULL) { 813 if (torture_type != NULL) {
815 pr_alert("%s: Refusing %s init 814 pr_alert("%s: Refusing %s init: %s running.\n",
816 __func__, ttype, tor 815 __func__, ttype, torture_type);
817 pr_alert("%s: One torture test 816 pr_alert("%s: One torture test at a time!\n", __func__);
818 mutex_unlock(&fullstop_mutex); 817 mutex_unlock(&fullstop_mutex);
819 return false; 818 return false;
820 } 819 }
821 torture_type = ttype; 820 torture_type = ttype;
822 verbose = v; 821 verbose = v;
823 fullstop = FULLSTOP_DONTSTOP; 822 fullstop = FULLSTOP_DONTSTOP;
824 torture_print_module_parms(); 823 torture_print_module_parms();
825 return true; 824 return true;
826 } 825 }
827 EXPORT_SYMBOL_GPL(torture_init_begin); 826 EXPORT_SYMBOL_GPL(torture_init_begin);
828 827
829 /* 828 /*
830 * Tell the torture module that initialization 829 * Tell the torture module that initialization is complete.
831 */ 830 */
832 void torture_init_end(void) 831 void torture_init_end(void)
833 { 832 {
834 mutex_unlock(&fullstop_mutex); 833 mutex_unlock(&fullstop_mutex);
835 register_reboot_notifier(&torture_shut 834 register_reboot_notifier(&torture_shutdown_nb);
836 } 835 }
837 EXPORT_SYMBOL_GPL(torture_init_end); 836 EXPORT_SYMBOL_GPL(torture_init_end);
838 837
839 /* 838 /*
840 * Clean up torture module. Please note that 839 * Clean up torture module. Please note that this is -not- invoked via
841 * the usual module_exit() mechanism, but rath 840 * the usual module_exit() mechanism, but rather by an explicit call from
842 * the client torture module. Returns true if 841 * the client torture module. Returns true if a race with system shutdown
843 * is detected, otherwise, all kthreads starte 842 * is detected, otherwise, all kthreads started by functions in this file
844 * will be shut down. 843 * will be shut down.
845 * 844 *
846 * This must be called before the caller start 845 * This must be called before the caller starts shutting down its own
847 * kthreads. 846 * kthreads.
848 * 847 *
849 * Both torture_cleanup_begin() and torture_cl 848 * Both torture_cleanup_begin() and torture_cleanup_end() must be paired,
850 * in order to correctly perform the cleanup. 849 * in order to correctly perform the cleanup. They are separated because
851 * threads can still need to reference the tor 850 * threads can still need to reference the torture_type type, thus nullify
852 * only after completing all other relevant ca 851 * only after completing all other relevant calls.
853 */ 852 */
854 bool torture_cleanup_begin(void) 853 bool torture_cleanup_begin(void)
855 { 854 {
856 mutex_lock(&fullstop_mutex); 855 mutex_lock(&fullstop_mutex);
857 if (READ_ONCE(fullstop) == FULLSTOP_SH 856 if (READ_ONCE(fullstop) == FULLSTOP_SHUTDOWN) {
858 pr_warn("Concurrent rmmod and 857 pr_warn("Concurrent rmmod and shutdown illegal!\n");
859 mutex_unlock(&fullstop_mutex); 858 mutex_unlock(&fullstop_mutex);
860 schedule_timeout_uninterruptib 859 schedule_timeout_uninterruptible(10);
861 return true; 860 return true;
862 } 861 }
863 WRITE_ONCE(fullstop, FULLSTOP_RMMOD); 862 WRITE_ONCE(fullstop, FULLSTOP_RMMOD);
864 mutex_unlock(&fullstop_mutex); 863 mutex_unlock(&fullstop_mutex);
865 torture_shutdown_cleanup(); 864 torture_shutdown_cleanup();
866 torture_shuffle_cleanup(); 865 torture_shuffle_cleanup();
867 torture_stutter_cleanup(); 866 torture_stutter_cleanup();
868 torture_onoff_cleanup(); 867 torture_onoff_cleanup();
869 return false; 868 return false;
870 } 869 }
871 EXPORT_SYMBOL_GPL(torture_cleanup_begin); 870 EXPORT_SYMBOL_GPL(torture_cleanup_begin);
872 871
873 void torture_cleanup_end(void) 872 void torture_cleanup_end(void)
874 { 873 {
875 mutex_lock(&fullstop_mutex); 874 mutex_lock(&fullstop_mutex);
876 torture_type = NULL; 875 torture_type = NULL;
877 mutex_unlock(&fullstop_mutex); 876 mutex_unlock(&fullstop_mutex);
878 } 877 }
879 EXPORT_SYMBOL_GPL(torture_cleanup_end); 878 EXPORT_SYMBOL_GPL(torture_cleanup_end);
880 879
881 /* 880 /*
882 * Is it time for the current torture test to 881 * Is it time for the current torture test to stop?
883 */ 882 */
884 bool torture_must_stop(void) 883 bool torture_must_stop(void)
885 { 884 {
886 return torture_must_stop_irq() || kthr 885 return torture_must_stop_irq() || kthread_should_stop();
887 } 886 }
888 EXPORT_SYMBOL_GPL(torture_must_stop); 887 EXPORT_SYMBOL_GPL(torture_must_stop);
889 888
890 /* 889 /*
891 * Is it time for the current torture test to 890 * Is it time for the current torture test to stop? This is the irq-safe
892 * version, hence no check for kthread_should_ 891 * version, hence no check for kthread_should_stop().
893 */ 892 */
894 bool torture_must_stop_irq(void) 893 bool torture_must_stop_irq(void)
895 { 894 {
896 return READ_ONCE(fullstop) != FULLSTOP 895 return READ_ONCE(fullstop) != FULLSTOP_DONTSTOP;
897 } 896 }
898 EXPORT_SYMBOL_GPL(torture_must_stop_irq); 897 EXPORT_SYMBOL_GPL(torture_must_stop_irq);
899 898
900 /* 899 /*
901 * Each kthread must wait for kthread_should_s 900 * Each kthread must wait for kthread_should_stop() before returning from
902 * its top-level function, otherwise segfaults 901 * its top-level function, otherwise segfaults ensue. This function
903 * prints a "stopping" message and waits for k 902 * prints a "stopping" message and waits for kthread_should_stop(), and
904 * should be called from all torture kthreads 903 * should be called from all torture kthreads immediately prior to
905 * returning. 904 * returning.
906 */ 905 */
907 void torture_kthread_stopping(char *title) 906 void torture_kthread_stopping(char *title)
908 { 907 {
909 char buf[128]; 908 char buf[128];
910 909
911 snprintf(buf, sizeof(buf), "%s is stop 910 snprintf(buf, sizeof(buf), "%s is stopping", title);
912 VERBOSE_TOROUT_STRING(buf); 911 VERBOSE_TOROUT_STRING(buf);
913 while (!kthread_should_stop()) { 912 while (!kthread_should_stop()) {
914 torture_shutdown_absorb(title) 913 torture_shutdown_absorb(title);
915 schedule_timeout_uninterruptib 914 schedule_timeout_uninterruptible(HZ / 20);
916 } 915 }
917 } 916 }
918 EXPORT_SYMBOL_GPL(torture_kthread_stopping); 917 EXPORT_SYMBOL_GPL(torture_kthread_stopping);
919 918
920 /* 919 /*
921 * Create a generic torture kthread that is im 920 * Create a generic torture kthread that is immediately runnable. If you
922 * need the kthread to be stopped so that you 921 * need the kthread to be stopped so that you can do something to it before
923 * it starts, you will need to open-code your 922 * it starts, you will need to open-code your own.
924 */ 923 */
925 int _torture_create_kthread(int (*fn)(void *ar 924 int _torture_create_kthread(int (*fn)(void *arg), void *arg, char *s, char *m,
926 char *f, struct ta 925 char *f, struct task_struct **tp, void (*cbf)(struct task_struct *tp))
927 { 926 {
928 int ret = 0; 927 int ret = 0;
929 928
930 VERBOSE_TOROUT_STRING(m); 929 VERBOSE_TOROUT_STRING(m);
931 *tp = kthread_create(fn, arg, "%s", s) 930 *tp = kthread_create(fn, arg, "%s", s);
932 if (IS_ERR(*tp)) { 931 if (IS_ERR(*tp)) {
933 ret = PTR_ERR(*tp); 932 ret = PTR_ERR(*tp);
934 TOROUT_ERRSTRING(f); 933 TOROUT_ERRSTRING(f);
935 *tp = NULL; 934 *tp = NULL;
936 return ret; 935 return ret;
937 } 936 }
938 937
939 if (cbf) 938 if (cbf)
940 cbf(*tp); 939 cbf(*tp);
941 940
942 wake_up_process(*tp); // Process is s 941 wake_up_process(*tp); // Process is sleeping, so ordering provided.
943 torture_shuffle_task_register(*tp); 942 torture_shuffle_task_register(*tp);
944 return ret; 943 return ret;
945 } 944 }
946 EXPORT_SYMBOL_GPL(_torture_create_kthread); 945 EXPORT_SYMBOL_GPL(_torture_create_kthread);
947 946
948 /* 947 /*
949 * Stop a generic kthread, emitting a message. 948 * Stop a generic kthread, emitting a message.
950 */ 949 */
951 void _torture_stop_kthread(char *m, struct tas 950 void _torture_stop_kthread(char *m, struct task_struct **tp)
952 { 951 {
953 if (*tp == NULL) 952 if (*tp == NULL)
954 return; 953 return;
955 VERBOSE_TOROUT_STRING(m); 954 VERBOSE_TOROUT_STRING(m);
956 kthread_stop(*tp); 955 kthread_stop(*tp);
957 *tp = NULL; 956 *tp = NULL;
958 } 957 }
959 EXPORT_SYMBOL_GPL(_torture_stop_kthread); 958 EXPORT_SYMBOL_GPL(_torture_stop_kthread);
960 959
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